//
// Created by ChaoDONG on 2021-03-24.
//

/* enum.c -- uses enumerated values */
#include <stdio.h>
#include <string.h> // for strcmp(), strchr()
#include <stdbool.h> // C99 feature

char * s_gets(char * st, int n);
enum spectrum {red, orange, yellow, green, blue, violet};
const char * colors[] = {"red", "orange", "yellow",
                         "green", "blue", "violet"};
#define LEN 30

int main(void)
{
    char choice[LEN];
    enum spectrum color;
    bool color_is_found = false;
    puts("Enter a color (empty line to quit):");
    while (s_gets(choice, LEN) != NULL && choice[0] != '\0')
    {
        for (color = red; color <= violet; color++)
        {
            if (strcmp(choice, colors[color]) == 0)
            {
                color_is_found = true;
                break;
            }
        }
        if (color_is_found)
            switch(color)
            {
                case red : puts("Roses are red.");
                    break;
                case orange : puts("Poppies are orange.");
                    break;
                case yellow : puts("Sunflowers are yellow.");
                    break;
                case green : puts("Grass is green.");
                    break;
                case blue : puts("Bluebells are blue.");
                    break;
                case violet : puts("Violets are violet.");
                    break;
            }
        else
            printf("I don't know about the color %s.\n", choice);
        color_is_found = false;
        puts("Next color, please (empty line to quit):");
    }
    puts("Goodbye!");
    return 0;
}

char * s_gets(char * st, int n)
{
    char * ret_val;
    char * find;
    ret_val = fgets(st, n, stdin);
    if (ret_val)
    {
        find = strchr(st, '\n'); // look for newline
        if (find) // if the address is not NULL,
            *find = '\0'; // place a null character there
        else
            while (getchar() != '\n')
                continue; // dispose of rest of line
    }
    return ret_val;
}